Related factors of negative conversion time of nucleic acid in children with COVID-19 / 中华儿科杂志

Objective: To explore the related factors of negative conversion time (NCT) of nucleic acid in children with COVID-19. Methods: A retrospective cohort study was conducted. A total of 225 children who were diagnosed with COVID-19 and admitted to Changxing Branch of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from April 3rd to May 31st 2022 were enrolled in the study. The infection age, gender, viral load, basic disease, clinical symptoms and information of accompanying caregivers were retrospectively analyzed. According to age, the children were divided into<3 years of age group and 3-<18 years of age group. According to the viral nucleic acid test results, the children were divided into positive accompanying caregiver group and negative accompanying caregiver group. Comparisons between groups were performed using Mann-Whitney U test or Chi-square test. Multivariate Logistic regression analysis was used to analyze the related factors of NCT of nucleic acid in children with COVID-19. Results: Among the 225 patients (120 boys and 105 girls) of age 2.8 (1.3, 6.2) years, 119 children <3 years and 106 children 3-<18 years of age, 19 cases were diagnosed with moderate COVID-19, and the other 206 cases were diagnosed with mild COVID-19. There were 141 patients in the positive accompanying caregiver group and 84 patients in the negative accompanying caregiver group.Patients 3-<18 years of age had a shorter NCT (5 (3, 7) vs.7 (4, 9) d, Z=-4.17, P<0.001) compared with patients <3 years of age. Patients in the negative accompanying caregiver group had a shorter NCT (5 (3, 7) vs.6 (4, 9) d,Z=-2.89,P=0.004) compared with patients in the positive accompanying caregiver group. Multivariate Logistic regression analysis showed that anorexia was associated with NCT of nucleic acid (OR=3.74,95%CI 1.69-8.31, P=0.001). Conclusion: Accompanying caregiver with positive nucleic acid test may prolong NCT of nucleic acid, and decreased appetite may be associated with prolonged NCT of nucleic acid in children with COVID-19.

Systematic review and Meta-analysis of efficacy and safety of Ningxinbao Capsules in treatment of arrhythmia / 中国中药杂志

To systematically evaluate the efficacy and safety of Ningxinbao Capsules in treatment of arrhythmia by Meta-analysis. Randomized controlled trial(RCT) or quasi-randomized control trial(Quasi-RCT) on Ningxinbao Capsules treating arrhythmia were obtained by computer-based retrieval in CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, Cochrane Library and EMbase as well as manual retrieval, with time limit from database establishment to April 7, 2020. According to the inclusion and exclusion criteria of trials, all RCTs were screened and evaluated. Then the effective data were collected and RevMan 5.3 Meta-analysis software was used for analysis. Thirteen trials were included, involving 1 379 patients in total. Ningxinbao Capsules combined with anti-arrhythmia Western medicine were adopted as the intervention, and the patients in control group were treated with the anti-arrhythmia Western medicine alone. Meta-analysis results showed that as compared to control group, Ningxinbao Capsules combined with anti-arrhythmia Western medicine group was superior in clinical efficacy, dynamic electrocardiogram and average heart rate in patients with bradycardia, with indicated statistically significant differences. Ningxinbao Capsules had fewer adverse reactions and could relieve the toxic and side effects of anti-arrhythmia medicine possibly. The study showed that Ningxinbao Capsules played a role in treatment of arrhythmia and was relatively safe. However, due to the limited quality of the included studies, high-quality clinical trials are needed to verify the conclusions.

Association between serum uric acid and large-nerve fiber dysfunction in type 2 diabetes: a cross-sectional study / 中华医学杂志(英文版)

Background:@#Large-nerve fiber dysfunction, as assessed by vibration perception threshold (VPT) predicts risks of ulceration, amputation, and mortality in diabetes. Serum uric acid (UA) is closely associated with various metabolic disorders, especially diabetes. Thus, we sought to investigate the clinical relevance of UA to large-nerve fiber dysfunction, among patients with type 2 diabetes (T2D).@*Methods:@#Medical records of consecutive patients with T2D who were admitted to Beijing Friendship Hospital Pinggu Campus between May 2014 and December 2016 were collected. Data for the 824 eligible patients included in the final analysis were extracted using a structured form. A VPT value ≥15 in either foot was defined as abnormal. We compared the clinical characteristics between patients with abnormal VPT and those with normal VPT (VPT value <15 in both feet) in the overall population and in gender subgroups. Logistic regression analysis was performed to explore the association of abnormal VPT with UA level. One-way analysis of variance was used to compare VPT values across four UA quartiles.@*Results:@#UA levels were significantly lower in T2D patients with abnormal VPT than in those with normal VPT (294.5 ± 84.0 vs. 314.9 ± 92.8 μmol/L, P < 0.01), especially among male patients (311.7 ± 85.2 vs. 336.9 ± 89.6 μmol/L, P < 0.01). From the logistic regression analysis, hyperuricemia (males >420 μmol/L; females >360 μmol/L) was associated with a reduced risk of abnormal VPT (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.39–0.91; P < 0.05). This association was robust in male patients (OR, 0.43; 95% CI, 0.24–0.76; P < 0.01) but not in female patients (OR, 0.92; 95% CI, 0.47–1.82; P = 0.816), even after adjustment for confounding factors. For the younger male subgroup (age <65 years), VPT values decreased as the UA level increased (P for trend = 0.002), but this trend was not significant in older male subgroup (age ≥65 years; P for trend = 0.400).@*Conclusions:@#Low serum UA levels showed a significant association with an increased risk of large-nerve fiber dysfunction in male patients with T2D, but not in female patients with T2D. In addition, in only the younger subgroup of male patients (<65 years), lower levels of UA also correlated with higher VPT values.

Research Progress of C-Myc in Chronic Myelogenous Leukemia --Review / 中国实验血液学杂志

As a potential target for cancer treatment, the C-Myc high expresses abnormally in a variety of solid tumors and hematological malignancies in humans. In hematologic malignancies, the increasing expression of C-Myc is associated with poor prognosis of patients diffuse large B-cell lymphoma. However, some studies have shown that high expression of C-Myc might be one of the mechanisms of disease progression and abrupt change, therefore, it can promote the transformation of chronic myeloid leukemia. Besides, the high expression of C-Myc may lead to the decrease of the sensitivity of chronic myelogenous leukemia cells to imatinib. Therefore, C-Myc has been concerned in the study of imatinib drug resistance. This review will focuses on the latest research progress on the mechanism of C-Myc in chronic myeloid leukemia in recent years.

Effects of Ubiquitination on the Expression of BCL6 Protein，Cell Proliferation and Apoptosis in K562/G01 Cells / 中国实验血液学杂志

OBJECTIVE@#To explore the the effects of ubiquitin-proteasome system (UPS) on BCL6 protein level，proliferation and apoptosis of cell imatinib（IM）-resistant K562/G01 cells.@*METHODS@#Western blot was used to detect the expression of BCL6 in K562/G01 cells before and after treatment with protease inhibitor MG-132.The RT-PCR and Western blot respectively were used to detect the mRNA and protein expression levels of BCL6 and USP2 in K562/G01 cells treated with or without ML364 (a ubiquitin-specific protease USP2 inhibitor). The effects of IM alone or in combination with ML364 on proliferation and apoptosis of K562/G01 were analysed by CCK-8 method and flow cytometry.@*RESULTS@#After treatment with protease inhibitor MG132, the BCL6 protein level of K562/G01 significantly increased (P<0.05). The mRNA and protein expression level of ubiquitin-specific protease USP2 in K562/G01 cell line was higher than that in K562 cell line (P<0.05). After treatment of K562/G01 with USP2 protease inhibitor ML364, the expression levels of USP2 and BCL6 proteins were down-regulated simultaneously (P<0.05) . After combination of ML364 and IM, both the proliferation inhibitory rate and the apoptosis rate of K562/G01 cells significantly increased(P<0.05).@*CONCLUSION@#ML364 decreases the BCL6 protein stability in K562/G01 by inhibiting the USP2-mediated deubiquitination, and down-regulate the BCL6 protein experssion, thereby increases the sensitivity of drug-resistant cells to IM.

Association between serum uric acid and large-nerve fiber dysfunction in type 2 diabetes: a cross-sectional study / 中华医学杂志(英文版)

BACKGROUND@#Large-nerve fiber dysfunction, as assessed by vibration perception threshold (VPT) predicts risks of ulceration, amputation, and mortality in diabetes. Serum uric acid (UA) is closely associated with various metabolic disorders, especially diabetes. Thus, we sought to investigate the clinical relevance of UA to large-nerve fiber dysfunction, among patients with type 2 diabetes (T2D).@*METHODS@#Medical records of consecutive patients with T2D who were admitted to Beijing Friendship Hospital Pinggu Campus between May 2014 and December 2016 were collected. Data for the 824 eligible patients included in the final analysis were extracted using a structured form. A VPT value ≥15 in either foot was defined as abnormal. We compared the clinical characteristics between patients with abnormal VPT and those with normal VPT (VPT value 420 μmol/L; females >360 μmol/L) was associated with a reduced risk of abnormal VPT (odds ratio [OR], 0.60; 95% confidence interval [CI], 0.39-0.91; P < 0.05). This association was robust in male patients (OR, 0.43; 95% CI, 0.24-0.76; P < 0.01) but not in female patients (OR, 0.92; 95% CI, 0.47-1.82; P = 0.816), even after adjustment for confounding factors. For the younger male subgroup (age <65 years), VPT values decreased as the UA level increased (P for trend = 0.002), but this trend was not significant in older male subgroup (age ≥65 years; P for trend = 0.400).@*CONCLUSIONS@#Low serum UA levels showed a significant association with an increased risk of large-nerve fiber dysfunction in male patients with T2D, but not in female patients with T2D. In addition, in only the younger subgroup of male patients (<65 years), lower levels of UA also correlated with higher VPT values.

Effect of GP130 small molecular inhibitor SC144 on renal interstitial fibrosis in mice with unilateral ureteral obstruction / 上海交通大学学报（医学版）

Objective·To investigate the effect of glycoprotein 130 (GP130) inhibitor SC144 on extracellular matrix accumulation and JAK2/STAT3 signaling pathway in unilateral ureteral obstruction (UUO) mouse model, and explore its mechanism. Methods·Eighteen female BALB/c mice were randomly divided into 3 groups i.e. sham group, UUO group and SC144 group. All mice were sacrificed at day 14 and kidneys were harvested for further analysis. The changes of renal tissue morphology and pathology were observed by H-E and Masson staining. The expression of α-smooth muscle actin (α-SMA) and infiltration of macrophage cells were assayed by immunohistochemical staining. The levels of collagen-I, collagen-IV, monocyte chemoattractant protein-1(MCP-1),transforming growth factor-β(TGF-β)mRNA were analyzed by real-time PCR.The activation of JAK2 and STAT3 was measured by Western blotting. Results·There was a trend toward decreased renal tubular lesion and renal interstitial fibrosis in SC144 group (H-E, P=0.052;Masson,P=0.063).SC144 significantly inhibited the levels of α-SMA,type I/type IV collagen and TGF-β mRNA(all P<0.05).Compared with UUO group, the phosphorylation levels of JAK2 and STAT3 were significantly decreased in SC144 group (both P<0.05). Conclusion·The treatment of UUO mouse model with SC144 can inhibit the activation of α-SMA, attenuate the phosphorylation of STAT3, reduce extracellular matrix protein deposition following injury and renal tubular epithelial-mesenchymal transition(EMT)via JAK2/STAT3 signaling pathway,indicating its potential in attenuating interstitial fibrosis in obstructive nephropathy.

Research Progress of β-catenin in Chronic Myelogenous Leukemia -Review / 中国实验血液学杂志

β-catenin is an important member of Wnt signaling pathway. With more and more research on the relationship between β-catenin and cancers, it is noted that the concentration of β-catenin in cells is not only the landmark of activating the Wnt signaling pathway, but also a common phenomenon in various tumor cells. Moreover, abnormal expression of β-catenin is reported in blastic phase of CML and IM-resistant CML. Besides, β-catenin inhibitor is proved to be effective for the improvement of the IM susceptibility and the postponment of blastic phase. Here is to make a brief review about the mechanisms of β-catenin in the treatment of CML, such as classical signaling pathways as well as new genes and pathways.

Mechanism of mTOR Pathway in K562 cell Apoptosis Induced by Homoharringtonine / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effect of homoharringtonine (HHT) on proliferation and apoptosis of CML cell line K562 cells and to explore its possible mechanism through mTOR pathway.</p><p><b>METHODS</b>K562 cells were cultured with different concentrations of HHT or in its combination with mTOR inhibitor rapamycin (RAPA) for 24 hours. The cell viability was analyzed by CCK-8 assay, the cell apoptosis was detected by flow cytometry, the expressions of BCL-6, Caspase-3 and mTOR signal pathway related proteins was assayed by Western blot, the expression of BCL-6 mRNA was determined by RT-PCR.</p><p><b>RESULTS</b>The HHT inhibited proliferation and induced apoptosis of K562 cells in a concentration-dependent manner(r=0.970). With the increasing of HHT concentration, the expression level mTOR signal pathway related proteins increased(r=0.908), while the mRNA and protein expression levels of BCL-6 decreased(r=-0.961, r=-0.981), as compared with the HHT alone, the combination of HHT with RAPA could down-regulate the expression of mTOR signal pathway related protein and caspase-3, and up-regulated expression of BCL-6.</p><p><b>CONCLUSION</b>HHT induces apoptosis of K562 cells by inhibiting BCL-6 expression through mTOR signal pathway.</p>

Research Progress of Homoharringtonine Effect on IM-resistant Chronic Myelogenous Leukemia -Review / 中国实验血液学杂志

Homoharringtonine(HHT) is an alkaloid with anti-tumor activity, having a good therapeutic effect on chronic myeloid leukemia(CML), and its toxicity is much lower than other anti-cancer drugs. However, the remarkable therapeutic efficacy of imatinib on CML treatment made HHT to be forgotten gradually. Today, the omacetaxine mepesuccinate, a semisynthetic form of HHT, display a good clinical response to TKI-resistant CML patients. Therefore, the HHT again attracts more attention from the medical field. Here, the clinical effects of HHT on IM-resistant CML patients and its mechanism are briefly reviewed.

Effect of Homoharringtonine Combined with Imatinib on the K562/G01 Cells and Its Mechanism / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effect of homoharringtonine(HHT) combined with imatinib(IM) on proliferation and apoptosis of K562/G01 cells and its potential mechanism.</p><p><b>METHODS</b>K562/G01 cells were cultured with HHT and/or IM. CCK-8 assay was used to detect cell proliferation. Cell apoptosis and phosphorylated tyrosine levels were analyzed by flow cytometry. The expression levels of p210, PI3K, p-Akt and Akt protein were determined by Western blot.</p><p><b>RESULTS</b>Compared with HHT or IM alone, drug combination significantly inhibited cell proliferation and induced apoptosis of K562/G01 cells (both P< 0.05). HHT combined with IM could inhibit the levels of phosphorylated tyrosine and phosphorylated Crkl and downregulate the expressions of p210, PI3K and p-Akt in K562/G01 cells.</p><p><b>CONCLUSION</b>HHT combined with IM can synergistically inhibit proliferation and induce apoptosis of K562/G01 cells by suppressing the p210 expression and its kinase activity.</p>

Progress of Researches on Prediction of Tyrosine Kinase Inhibitor Efficacy for Treatment of Chronic Myelocid Leukemia -Review / 中国实验血液学杂志

Tyrosine kinase inhibitors (TKI) have made a dramatic improvement in the clinical efficacy of chronic myelogenous leukemia, but the occurrence of TKL resistance and intolerance does not enable some patients to acquire the satisfactory efficacy. Screening the proper TKL for patients with high risk before the treatment and conversing drug timely based on early detection of TKL resistance are helpful to accurately use TKI and enhance therapeutic efficacy. In this article, the function of some indicators, such as baseline clinical, biochemical and molecular biological characteristics and influence of early treatment response law of imatinib on long-term prognosis of newly diagnosed patients are summarized.

Effect of Autophagy on Homoharringtonine-treated K562 Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To study the effect of homoharringtonine (HHT) alone or combined with 3-methyladenine (3-MA) , an autophagy inhibitor, on the apoptosis and autophagy of K562 cells.</p><p><b>METHODS</b>K562 cells were treated with HHT(10 ng/ml) or HHT(10 ng/ml) combined with 3-MA (1.5 mmol/L) for 1 to 8 days. The apoptosis of treated cells was tested by means of flow cytometry(FCM), and the autophagy levels were tested with RT-PCR, Western blot and electron microscopy.</p><p><b>RESULTS</b>In the early stage of HHT-treated group, the apoptosis rate increased and decreased later. Beclin1 mRNA expression level and the LC3II/I ratio were declined firstly and increased later in HHT group. While combining with autophagy inhibitor 3-MA, both the Beclin1 mRNA expression level and the LC3II/I ratio were declined continually during the treated period. The activated caspase-3 protein expression level was also raised sustainability during both HHT and 3-MA cultured period.</p><p><b>CONCLUSIONS</b>HHT can induce apoptosis of K562 cells, but the sustaining effect of HHT can induc autophagy of K562 cells, the combination of HHT with 3-MA may enhance the cytotoxicitic effect of HHT on K562 cells.</p>

Acadesine Inhibits the Proliferation of K562 Cells and Enhances their Sensitivity to Imatinib / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the effects of AMPK agonist Acadesine (AICAR) on growth inhibition of K562 cells and their sensitivity to imatinib (IM).</p><p><b>METHODS</b>K562 cells were cultured with different concentrations of AICAR alone or its combination with IM for 48 hours, the CCK-8 assay was used to detect cell proliferation, the cell cycle distribution and apoptosis were analyzed by flow cytometry. The expression levels of Cyclin D1, Cyclin E1 and Caspase 3 protein were determined by Western blot.</p><p><b>RESULTS</b>AICAR inhibited the proliferation of K562 cells in dose-dependent manner, and their IC50 value was 0.45 mmol/L at 48 hours. AICAR could induce arrest of K562 cells in G1 phase and down-regulated the protein expression levels of Cyclin D1 and Cyclin E1; whereas it didn't influence the cell apoptosis. Additionally, the growth inhibition of cells induced by IM was enhanced by AICAR.</p><p><b>CONCLUSION</b>AICAR can inhibit the proliferation of K562 cells by arresting the cell cycle and enhancing the sensitivity of K562 cells to IM.</p>

Effects of Homoharringtonine Combined with Imatinib on K562 Cell Apoptosis and BCL6 expression / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To explore the effects of homoharringtonine (HHT) alone or combined with imatinib (IM) on K562 cell proliferation and apoptosis, as well as the mRNA and protein expression of BCL6.</p><p><b>METHODS</b>The CCK-8 was used to detect the inhibitory effect of drugs on cell growth, the flow cytometry was used to detect the cell apoptosis. The expression of BCL6 protein was assayed by Western blot, and BCL6 mRNA expression was detected by RT-PCR.</p><p><b>RESULTS</b>HHT alone displayed a proliferation inhibition effect with dose- dependent manner, and induced apotosis; after combination of HHT and IM drugs, both the inhibitory rate and the apoptosis rate were significantly increased compared with the drug alone(P<0.05). Western blot showed that the expression of BCL6 protein was down-regulated after being treated with HHT, however, the BCL6 protein was up-regulated after being treated with IM . The effect of drug combination showed that BCL6 protein significantly down-regulated(P<0.05 ). The expression of BCL6 mRNA was decreased both in the treatment of HHT or IM alone when compared with control. And the effect of drug combination showed that BCL6 mRNA expression was more significantly down-regulated(P<0.05 ).</p><p><b>CONCLUSION</b>HHT can inhibit the K562 cell proliferation and induce apoptosis of K562 cells. Combination of IM with HHT shows a significant synergistic effect, the mechanism may be associated with down-regulation of BCL6.</p>

Effect of YM155 on Apoptosis and Autophagy of K562 Cells / 中国实验血液学杂志

<p><b>OBJECTIVE</b>This study was purposed to investigate the effect of YM155, a survivin inhibitor, on the apoptosis and autophagy of K562 cells.</p><p><b>METHODS</b>K562 cells were treated with YM155 at different concentration. Cell survival was analyzed by CCK-8 assay, the cell apoptosis was detected by flow cytometry. Survivin, BCL-2 and beclin1 mRNA expressions were determined by RT-PCR. Survivin, BCL-2, caspase-3, PARP and LC-3 protein expressions were assayed by Western blot.</p><p><b>RESULTS</b>YM155 inhibited the proliferation of K562 cells in a time- and dose-dependent manners. With the increasing of YM155 concentration and prolonging of action time, the expression levels of mRNA and protein of survivin and BCL-2 decreased, while the expression levels of caspase-3, PARP, beclin1 and LC-3 increased. Compared with the YM155 group, the protein levels of LC-3 and caspase-3 were lower in YM155 combined with 3-MA group.</p><p><b>CONCLUSION</b>YM155 can inhibit K562 cell proliferation by inducing apoptosis and autophagy, while autophagy induction effect can enhance its cytotoxic effect.</p>

Effect of compound Chinese traditional medicine PC-SPES II in inhibiting proliferation of human prostate cancer cell LNCaP and on expressions of AR and PSA / 中国中药杂志

To investigate the effect of compound Chinese traditional medicine PC-SPES II I in inhibiting proliferation of human prostate cancer cell LNCaP based on the androgen receptor (AR) signaling pathway. The effect of PC-SPES II on LNCaP cell proliferation was detected by MTT assay. According to the findings, at the mass concentration of 180-1 440 mg x L(-1), PC-SPES II significantly inhibited the proliferation of LNCaP cells; the IC50 of PC-SPES II at 24 h and 48 h were 311.48, 199.01 mg x L(-1), respectively. The flow Cytometry detection showed 240 mg x L(-1) PC-SPES II arrested cells in G2/M phase, and an obvious apoptotic peak appeared before G0/G1 peak and rose over time. Meanwhile, Hoechst 33258 staining revealed apoptotic cellular morphology. Annexin V-FITC/PI staining manifested an increase in apoptotic cell ratio at the PC-SPES II concentration of 480 mg x L(-1) in a dose dependent manner. The prostate specific antigen (PSA) secretion of LNCaP cells was tested by PSA ELISA kit. Besides, compared with 25 mg x L(-1) Bic, 480 mg x L(-1) PC-SPES II significantly reduced the cell secretion of PSA. The AR and PSA mRNA and protein expressions were detected by qRT-PCR and Western blot. According to the results, after the induction of LNCaP cells with synthetic androgen 25 μg x L(-1) R1881, 240-480 mg x L(-1) PC-SPES II notably down-regulated the AR and PSA mRNA and protein expressions and inhibited the translocation of AR from cytoplasm to nucleus. In summary, PC-SPES II significantly can inhibit the in vitro proliferation of LNCaP cells and arrest cell cycle arrest in G2/M phase. Its mechanism may be associated with the down-regulation of the AR and PSA expressions and the inhibition of AR nuclear translocation.

Effect of mouse oocyte vitrification on mitochondrial membrane potential and distribution / 华中科技大学学报（医学）（英德文版）

The effects of mouse oocyte vitrification on mitochondrial membrane potential and distribution were explored in this study. The collected mouse oocytes were randomly divided into vitrification and control groups. Ethylene glycol (EG) and dimethylsulphoxide (DMSO) were used as cryoprotectants in the vitrification group. The mitochondrial function and distribution in the oocytes were examined by using the fluorescent probes, JC-1 and Mito Tracker green. The results showed that the ratio of red to green fluorescence in mouse oocytes was significantly decreased after thawing in the vitrification group as compared with the control group (1.28 vs. 1.70, P<0.05). The percentage of polarized distribution of the mitochondria in oocytes was conspicuously reduced in the vitrification group when compared with the control group (31% vs. 63%, P<0.05). It was suggested that vitrification significantly affects the mitochondrial function and distribution in oocytes and reduces the potential of oocyte fertilization and embryo development.

Effect of mouse oocyte vitrification on mitochondrial membrane potential and distribution / 华中科技大学学报（医学）（英德文版）

The effects of mouse oocyte vitrification on mitochondrial membrane potential and distribution were explored in this study. The collected mouse oocytes were randomly divided into vitrification and control groups. Ethylene glycol (EG) and dimethylsulphoxide (DMSO) were used as cryoprotectants in the vitrification group. The mitochondrial function and distribution in the oocytes were examined by using the fluorescent probes, JC-1 and Mito Tracker green. The results showed that the ratio of red to green fluorescence in mouse oocytes was significantly decreased after thawing in the vitrification group as compared with the control group (1.28 vs. 1.70, P<0.05). The percentage of polarized distribution of the mitochondria in oocytes was conspicuously reduced in the vitrification group when compared with the control group (31% vs. 63%, P<0.05). It was suggested that vitrification significantly affects the mitochondrial function and distribution in oocytes and reduces the potential of oocyte fertilization and embryo development.

Time rhythm of homoharringtonine inducing K562 cell apoptosis and its mechanism / 中国实验血液学杂志

This study was aimed to explore the change of K562 cell apoptosis at different time point after homoharringtonine (HHT) treatment and its mechanism. After treatment of K562 cells with 10 ng/ml HHT, the cell viability was tested with MTT assay; the expression of caspase-3 was detected with Western blot; the BCL-2 expression was analyzed with flow cytometry; the autophagosome was observed by electron microscopy. The results showed that the viability of K562 cells reduced gradually from day 1 to day 5 and ascended from day 6 to day 8 after HHT treatment. At the same time, the cleaved caspase-3 expression level of K562 cells increased gradually from day 1 to day 7, but reduced at the day 8 (P < 0.05). From day 1 to day 8 after HHT treatment, the BCL-2 expression level declined firstly and then went up (P < 0.05). Autophagosome was also seen remarkably at day 8 after HHT treatment. It is concluded that the apoptosis level of K562 cells after being treated with HHT enhances firstly and then declines , which may be associated with higher autophagy level in the late stage of HHT treatment.